Of course that's right, sometimes that happends and it depends on your line of work. For me personally it's super seldom and 75% of what I learned in university I never used. That said, for me it was more learning how to think and approach problems what really made university worth for me.
I watched a lot of opencourseware material, and I think I used more often the knowledge that's about the limits of the field (IT), but I don't mind the time spent on datastructures either, even though I can't code fusion trees from memory ☺️.